The present invention relates generally to a door opening and closing apparatus for the opening and closing of a door of a refrigerator or the like, and more particularly, to a door opening and closing apparatus for enabling a door to be opened and closed in either of opposite directions, e.g., swinging to the left or to the right.
Generally, a door for a refrigerator or the like can be opened only from the left or right and then closed by reversing the action. Thus, when purchasing a refrigerator with such a door, the opening/closing direction of the door should be considered in advance to satisfy the ultimate needs or tastes of the user and the installation requirements in view of existing walls or other obstructions which may interfere with the door's operation. Also, when moving and/or reinstalling the refrigerator, there is a considerable limitation with regard to the relocation site. Thus, it is desirable that the refrigerator be equipped with a door which can be opened and closed in either direction.
A conventional apparatus which enables the opening and closing of a door in either of opposite directions is disclosed in U.S. Pat. No. 5,052,151, and is described below with reference to FIGS. 1, 2, 3A and 3B.
With reference now to FIG. 1, there can be seen a refrigerator having a body 2 to which a door 1 is attached. Hinge plates 3 each of which has a hinge shaft 4 are installed at the left and right corners of the upper and lower portions of the front of the refrigerator body 2, respectively. Notches 5 are formed in the door 1 so that each hinge shaft 4 can be engaged with and disengaged from the corresponding notch.
As shown in FIG. 2, an upper fixing plate 6 and a lower fixing plate 8 are mounted to upper and lower inner portions, respectively, of the door 1 in opposed relationship to each other, in correspondence to left and right hinge shafts 4a and 4b of hinge plates 3a and 3b. Latch plates 9a and 9b having latch grooves 10a and 10b for engaging hinge shafts 4a and 4b, respectively, are pivotally supported in the left and right sides of the door between the upper fixing plate 6 and the lower fixing plate 8. The respective rotation positions of the latch plates 9a and 9b are maintained by virtue of the biasing force of springs 11a and 11b. Pitching links 12a and 12b and connection link provide a mutual interlocking of latch plates 9a and 9b. Cover plates 14a and 14b are pivotally supported so as to cover openings 7a and 7b of the upper fixing plate 6.
As shown in FIG. 3A, if the door 1 is closed, hinge shafts 4a and 4b are inserted and locked into openings 7a and 7b of the upper fixing plate 6 and into latch grooves 10a and 10b of the latch plates 9a and 9b, respectively. Also, since springs 11a and 11b block the rotation of the latch plates 9a and 9b, the door 1 is maintained in the closed state. If the left side of the door 1 is pulled from the closed state, the latch plate 9a is forcibly rotated by the pulling action. Accordingly, the latch groove 10a is opened as shown in FIG. 3B. In this case, the altered rotation position of the latch plate 9a is maintained by spring 11a, and the rotation position of the other latch plate 9b is not altered in the door 1, due to the action of the pitching links 12a and 12b and the connection link 13 in response to the rotation of the latch plate 9a. Thus, door 1 pivots on the hinge shaft 4b of the other side for opening and closing. The above operation is identical for each side of door 1 due to its symmetrical construction.
In the above-described conventional apparatus, to ensure that the hinge shafts are inserted into and released from the latch grooves with precision and thereby provide for quiet and smooth operation, the rotation positions of the latch plates which are changed in accordance with the opening and closing of the door must be exactly maintained. Thus, the use of the aforementioned springs is required in order to secure the rotation positions of the latch plates. Also, a very small clearance between the working components is required during operation. However, since the cumulative clearance becomes large, particularly due to component wear over time, malfunction is frequent, and since the number of necessary components is great, assembly is complex and inefficient. Moreover, since the latch plate of one side is forcibly rotated in a desired direction when opening and closing the door, a force exceeding that of the spring of the latch plate is required. Thus, when opening and closing the door, strenuous effort is required and the smooth and quiet manipulation thereof is nearly impossible.